Pavement breaker



Feb. 22, 1966 BARNES 3,236,314

PAVEMENT BREAKER Filed April 12, 1952 2 SheetsSheet 1 INVENTOR. Harry 7? 3%7'7725 w); Ks:

Feb. 22, 1966 H. T. BARNES PAVEMENT BREAKER 2 SheetsSheet 2 Filed April 12, 1962 n 1 i J 5 J y Vi 4 1 M W United States Patent 3,236,314 PAVEMENT BREAKER Harry '1. Barnes, Oak Park, Mich, assiguor to Braco Equipment (10., Oak Park, Mich, a corporation of Michigan Filed Apr. 12, 1962, Ser. No. 186,918 2 Claims. (Cl. 17337) for operation and coordination with the conventional power system and controls incorporated therein.

Another object'of the present invention is to provide an improved pavement crusher which is adapted for mounting on conventional power cranes and shovels in place of the crane boom or shovel boom, thereby substantially increasing the flexibility and versatility of such heavy construction machinery.

Still another object of the present invention is to provide an improved pavement breaker which, when not in use, can be readily set up in a standby condition from which it can be simply mounted on a power crane or shovel with minimal time and effort.

A further object of the present invention is to provide an improved pavement breaker which is of simple and compact design, of durable and rugged construction, of economical manufacture and use, and which provides flexibility and versatility in operation unobtainable in machinery of similar type heretofore known.

The foregoing and other objects and advantages of the present invention are achieved by providing a pavement breaker comprising a framework incorporating guide means thereon along which a drop hammer is mounted and movable to and from a lowered impact position to a raised position by a power-lift cable readily connectible thereto as incorporated in conventional power shovels and cranes. Mounting means are provided on the framework for simply and quickly removably connecting the pavement breaker to the boom base connector and further incorporates means for connecting the boom hoist cables thereto for angularly tilting and lifting the framework relative to the ground. The pavement breaker is provided with retractable jack pads and skids along the base of the framework for storing the pavement breaker in an upright position when not in use.

Other objects and features of novelty of the invention -will be specifically pointed out or will become apparent when referring, for a better understanding of the invention, to the following description taken in conjunction with the accompanying drawings, wherein:

FIGURE 1 is a side elevational view of a pavement breaker constructed in accordance with the preferred embodiments of the present invention mounted on and operatively connected to a typical crawler type power crane;

FIG. 2 is a fragmentary perspective view, with portions broken away for clarity, of the drop hammer and guide rail assembly of the pavement breaker shown in FIG. 1 as viewed in the direction of the arrow indicated at 2;

FIG. 3 is a fragmentary perspective view of the rear and side of the pavement breaker shown in FIG. 1, and

FIG. 4 is a side elevational view of the pavement 3,236,314 Patented Feb. 22, 1966 breaker with the jack pad-s extended for storing the pavement breaker in an upright position when not in use.

Referring now in detail to the drawings, a pavement breaker constructed in accordance with the preferred embodiments of the present invention is shown in FIG. 1 removably mounted on a full-track or crawler type power crane. The exemplary power crane illustrated in FIG. 1 to which the present invention is applicable, comprises a crawler chassis 10 including a pair of'spaccd tracks 12 which are trained around a drive sprocket 14and an idler sprocket 16. The drive sprocket 14 is drivingly connected to a power plant (not shown) in a cab 18 of the power crane, such as by a drive chain, for example, in a manner well known to those skilled in the art. The cab 18 is rotatably mounted on the crawler chassis 10 by means of a ring gear and roller assemblygenerally indicated at 20, enabling swinging movement of thecab and the pavement breaker connected theretorelative) to the chassis.

Suitable power means (not shown), such as a gasoline or diesel engine, is mounted within the cab 18 and is drivingly connected to a seriesof cable drums, such as a cable drum 22 shown in FIG-1, which is selectively operable by the operator through suitable brake and clutch mechanisms for effecting actuation of a boom hoist cable 24 and a lift cable 26 in accordancewith the specific operation function desired. The boom hoist cable .24 is trained over a pair of sheaves 28 on a back-hitch gantry 30 and extends therefrom into the interior of the cab and around a power driven cable drum 31. The lift cable 26 is trained around the cable drum 22 -in.a manner as shown in FIG. 1 and is operative to effect a lifting and free fall of the drop hammer of the pavement crusher in a manner'a-s will be subsequently described.

The forward or right-hand portion of the 'cab .18 of the power crane as viewed in FIG. 1 is formed witha boom attachment 32 comprising a pair of spaced plates having a plurality of apertures 34- therein for pivotally securing and removably mounting the end portion-0f a crane boom, a shovel boom, or the pavement breaker as shown in FIG. 1. A suitable locking pin 36 is adapted to be disposed within the apertures 34 having the shank portion thereof extending through a suitable aperture in the mounting end of a boom or the pavement breaker, enabling simple attachment and detachment of the assembly while concurrently providing for angular tilting movement thereof relative to the power crane.

The pavement breaker as shown in. the drawings cornprises a framework including a pair of upright members 38 disposed in spaced substantially parallel relationship to which a series of longitudinally spaced rectangular frames 40 are rigidly secured such as by welding, for example. The frames 40 are preferably comprised of members of an I-beam cross section and are rigidly secured to each other at the ends thereof, such as by welding, as shown in FIG. 2.

A pair of rearwardly extending members .42 is rigidly secured to the upright members 38 at a point corresponding substantially to that at which a rectangular frame 40 is attached. The rearward end portion of the members 42 is provided with an aperture 44 for removably and slidably receiving the securing pin 36 for removably mounting the pavement breaker on the boom attachment 32.

The rearwardly extending members 42 are rigidly braced by diagonal members 46 extending angularly upwardly therefrom and rigidly afiixed to the upright members 38. The diagonal members are further reinforced by an X-frame 48 rigidly secured to and extending therebetween. The lower portions of the members 42 are rigidified by diagonal members 50 incorporating an X- frame 52 therein.

A pair of guide rails 54 is rigidly secured to the inner 3 surfaces of the frames 40 in a manner as may be best seen in FIGS. 1 and 2 and serves to slidably and guidably support a drop hammer or impact hammer 56 slidably mounted therebetween. The guide rails 54 are preferably of an H-shaped cross section and are positioned with the webs thereof disposed in Opposing substantially parallel spaced relationship.

The drop hammer 56 is formed with a pair of grooves 58 extending longitudinally along opposite sides thereof which are adapted to slidably coact with the web portions of the guide rails 54, restricting undesirable lateral and transverse movement of the drop hammer relative to the guide rails. The drop hammer 56 is formed with a cavity 60 in the upper end thereof, as best seen in FIG. 2, in which the loop end of the lift cable 26 is adapted to be disposed and removably secured therein by means of a pin 62 extending therethrough. The side portions of the body of the drop hammer 56 adjacent to the ends of the pin 62 are preferably formed with elongated recesses indicated at 64 for providing clearance for the projecting end portions of the pin 62.

In the exemplary drop hammer 56 illustrated in the drawings, a removable nose section 66 is provided which further increases the flexibility of the pavement breaker comprising the present invention. The nose section 66 is removably secured to the body of the drop hammer 56 by means of a pair of U-bolts 68 having the shank and bight portion thereof positioned in a U-shaped engaging cavity 70 along the sides of the body of the drop hammer whereby the shank end portions thereof project through a flange 72 of the nose section on which a series of nuts 74 are threadably engaged for securely clamping the nose section to the base of the body of the drop hammer. By virtue of this construction, the nose section 66 can be readily interchanged or replaced 'in the event of fracture or breakage or to enable mounting of a nose section having an optimum nose configuration consistent with a specific type of breaking operation to beperformed.

Movement of the drop hammer to a raised position enabling free fall thereof to the lowered position is achieved by the lift cable 26 in accordance with the operation of the cable drum 22 as controlled by the operator in the cab 18. The lift cable 26 extends upwardly and cent-rally of the guide rails 56 and is trained over a sheave 76 rotatably mounted on a cross member 78 rigidly aflixed to the upper ends of the guide rails 54 and the uppermost rectangular frame 40. Angular tilting movement of the pavement breaker about the pin 36 providing for relative vertical adjustment of the base of the pavement breaker relative to the surface to be crushed is accomplished by the boom hoist cables 24 which are trained about sheaves 80 rotatably mounted on a shaft 82 removably mounted and extending between the upright members 38.

It will be apparent from the foregoing that the simplicity of the construction and the ease of attachment thereof to the boom attachment of conventional power cranes provides for extreme versatility in the use of the pavement breaker comprising the present invention as well as increasing the efficiency and versatility of the power crane itself.

The pavement breaker, when not in use, can simply be stored in an upright standby position, as shown in FIG. 4, and in which position it can readily be connected to or disconnected from a power crane. In order to provide stability to the pavement breaker while in the storage position, ajpair of adjustable props 84 having base pads 86 along the bottoms thereof are slidably mounted along the outer portions of the rearwardly extending members 42 by means of sleeve brackets 88 rigidly afiixed to the outer surfaces thereof. The shafts of the props 84 are slidably disposed within the sleeve .brackets 88 and are movable therein to and from a raised position as shown in FIG. 3 during operation or use of the pavement breaker to a lowered position as shown in FIG. 4 when the pavement breaker is in a stored position. The shafts of the jacks 84 are provided with a plurality of apertures 90 extending transversely therethrough at longitudinally spaced intervals through which a locking pin 92 extending through the body of the sleeve bracket 88 is adapted to be inserted for restricting relative longitudinal and rotational movements of the jacks relative to the members 42. To further increase the stability and prevent any appreciable embedding of the pavement breaker, particularly in relatively soft earth, the lower portions of the guide rails 54 are preferably provided with a pair of skids 94, as may be best seen in FIGS. 2 to 4, which reduce the bearing pressure of the assembly when in the stored position.

In operation and with the pavement breaker in the stored position as shown in FIG. 4, the pavement breaker is connected to the boom attachment of a power crane by simply advancing the crane so that the boom attachment thereon is positioned adjacent to the apertures 44 at the ends of the members 42. The pins 36 are thereafter inserted through the mutually aligned apertures 34 in the boom attachment 32 and the apertures 44 in the rearwardly extending members 42. The lifting cable 26 is thereafter trained about the sheave 76 and removably connected to the drop hammer 56 by inserting the pin 62 through the looped end portion thereof. The boom hoist cables 24 are thereafter connected around the sheaves and the props 84 are withdrawn to the inoperative position as shown in FIG. 1. The pavement breaker may thereafter be lifted wherein the skids 94 along the lower portion thereof are raised above the ground and the drop hammer 56 is lifted to the raised position from which it is allowed to fall through the action of gravity elfecting a high pressure impact on the pavement or frozen ground, and the like, which is desired to be broken. The pavement breaker is simply disconnected from the power crane by reversing the steps hereinabove set forth.

While it will be apparent that the embodiment of the invention herein disclosed is well calculated to fulfill the objects of the invention, it will be appreciated that the invention is susceptible to modification, variation and change without departing from the proper scope or fair meaning of the subjoined claims.

What is claimed is:

1. In an apparatus for breaking pavement and the like, a framework embodying a plurality of spaced rectangular frame members, a pair of guide members secured in spaced aligned relation on the inner opposite faces of said frame members, a drop hammer having recesses on two opposite sides which receives said guide members, a sheave rotatably supported on the top of said guide members with one edge substantially aligned with the center of said drop hammer, reinforced attaching arms extended from one side of said framework for pivotal connection to a boom attachment of a power crane, means on said drop hammer to which a cable from the power crane is connectable when extending over said sheave, support means on the bottom of said guide members, and adjustable supporting means on said arms having a foot pad movable to and from the plane of said support means.

2. In an apparatus for breaking pavement and the like, a framework embodying a plurality of spaced rectangular frame members, a pair of guide members secured in spaced aligned relation on the inner opposite faces of said frame members, a drop hammer having recesses on two opposite sides which receives said guide members, a sheave rotatably supported on the top of said guide members with one edge substantially aligned with the center of said drop hammer, reinforced attaching arms extended from one side of said framework for pivotal connection to a boom attachment of a power crane, means on said drop hammer to which a cable from the power crane is connectable when extending over said sheave, support means on the bottom of said guide members, adjustable supporting means on said arms having a foot pad movable to and from the plane of said support means, and sheaves carried by said framework which are engageable by the hoist cables of the power crane.

References Cited by the Examiner Templeton 17337 Pegno 29937 Roland 175154 Kromberg 17337 X CHARLES E. OCONNELL, Primary Examiner. BENIAL'IIN HERSH, Examiner. 

1. IN AN APPARATUS FOR BREAKING PAVEMENT AND THE LIKE, A FRAMEWORK EMBODYING A PLURALITY OF SPACED RECTANGULAR FRAME MEMBERS, A PAIR OF GUIDE MEMBERS SECURED IN SPACED ALIGNED RELATION ON THE INNER OPPOSITE FACES OF SAID FRAME MEMBERS, A DROP HAMMER HAVING RECESSES ON TWO OPPOSITE SIDES WHICH RECEIVES SAID GUIDE MEMBERS, A SHEAVE ROTATABLY SUPPORTED ON THE TOP OF SAID GUIDE MEMBERS WITH ONE EDGE SUBSTANTIALLY ALIGNED WITH THE CENTER OF SAID DROP HAMMER, REINFORCED ATTACHING ARMS EXTENDED FROM ONE SIDE OF SAID FRAMEWORK FOR PIVOTAL CONNECTION TO A BOOM ATTACHMENT OF A POWER CRANE, MEANS ON SAID DROP HAMMER TO WHICH A CABLE FROM THE POWER CRANE IS CONNECTABLE WHEN EXTENDING OVER SAID SHEAVE, SUPPORT MEANS ON THE BOTTOM OF SAID GUIDE MEMBERS, AND ADJUSTABLE SUPPORTING MEANS ON SAID ARMS HAVING A FOOT PAD MOVABLE TO AND FROM THE PLANE OF SAID SUPPORT MEANS. 